update CMakeLists.txt to fix CMake build
update CMakeLists.txt to fix CMake build

lostdj/avian,bgould/avian,joshuawarner32/avian,minor-jason/avian,bgould/avian,marcinolawski/avian,bigfatbrowncat/avian-pack.avian,lwahlmeier/avian,ucdseniordesign/avian,lostdj/avian,dicej/avian,ucdseniordesign/avian,marcinolawski/avian,marcinolawski/avian,lostdj/avian,lwahlmeier/avian,ucdseniordesign/avian,ucdseniordesign/avian,minor-jason/avian,joshuawarner32/avian,marcinolawski/avian,bigfatbrowncat/avian-pack.avian,dicej/avian,joshuawarner32/avian,bigfatbrowncat/avian-pack.avian,minor-jason/avian,lwahlmeier/avian,MaartenR/avian,bigfatbrowncat/avian-pack.avian,lwahlmeier/avian,MaartenR/avian,MaartenR/avian,MaartenR/avian,minor-jason/avian,bgould/avian,dicej/avian,joshuawarner32/avian,bgould/avian,dicej/avian,lostdj/avian